hard starting

[jag7720]

I have an 85 CUCV with about 50k miles.

I just put on a freshly rebuilt IP, new glow plugs, new glow plug relay. I have a spin on filter and an electric lift pump that is on the frame rail mid-truck so it pushes fuel thru the filter to the IP. There is also a one-way valve before the filter so fuel will not roll back to the tank

Here is my issue.... First thing in the morning or if it has sat for a few hours, the truck will fire right up and run for maybe 5-10 seconds then die.

Then I have to crank and crank for several 30 second cycles before is starts to kick over and runs fine.

This tells me there is air in the lines/pump but I don't know where it is coming from. there is no fuel on the ground under the truck.

All this was happening before the new IP. The pump rebuilder told me the pump probably had a loose (I don't know the actual name for it) main shaft/rotor.


I'm ready to just sell it ....


Anyone know what might b going on? I don't know what to do at this point.

 

[Matt65]

Can you verify good stable pressure at your fuel filter supplied by your lift pump? 7 psi is in the ballpark iirc. Be careful with extended cranking, the starter will thank you.

 

[jag7720]

I cannot.
I don't have any sort of pressure gauge.... I have a mini-vac hand vacuum pump.. but I don't think that will help

I can hear the pump clicking like it always has when it is on.

 

[ryan77]

I would throw a inline electric pump in and replace the rubber lines and go from there!

 

[ryan77]

Remove the old mechanical pump and use a small block chevy fuel pump block off plate from autozone!

 

[kipman]

He states he has a electric pump, I think the " check valve" he put in is causing problems. I put a electric fuel pump on my 1009, no other check valve needed, mine is also on the frame rail about half way back. Try this, with the ignition on, and fuel pump working open a bleeder to check for air.

 

[DriverSideImpact1008]

Yeah, I agree with KIP. It sounds like you are getting air in the lines before the fuel pump. And just because you fuel pump is "clickin away like it always has" doesn't mean it is good. Cracking the bleeder and checking for air and flow is where I'd start.

I saw something in the TM for checking the flow rate; It was something along the lines of "Get a bottle, graduated cylinder, or something. Crank for X seconds and you should have X oz/mL or something like that.

 

[sandcobra164]

I broke a fuel line to the flame heater on my Deuce one time and wound up with the exact same symptoms. I know, different everything but one thing stayed the same. It'd start right up after a long sit but stall out after a few seconds. It'd come back to life after a bit of cranking. The lift pump is good, but after it's sat a while, the pressure bleeds off and the air get's introduced in the fuel line. It starts right up due to the fuel still in the IP, then the air get's in, you have a stall and then a long cranking time before it starts back up. I had no leaks from the cracked fuel inlet lines either.

 

[jag7720]

ok. I ditched my old walbro and slapped on a new Mr. Gasket pump. I also picked up a pressure tester from HF.

I wasn't able to get any pressure readings on the gauge for a long time... I ended up taking the line off the IP and putting the pressure gauge on it... still no pressure. I spun open the filter and got some air out of it... then spun off the gauge and got more air out.... then the pressure gauge jumped up to about 8 psi.

I took it for a 30 min highway drive and then let is sit for 3 hours... it started right up and didn't die.

Now the longer test of letting it sit over night.

 

[kipman]

Hope it keeps going like the energizer bunny.

 

[Cucvnut]

so your having no issues with your mr gasket pump? how close is it to the tank? I cant get mine to idle. I think its to far from the tank to supply proper pressure.

 

[ryan77]

I would get a electric one for a civi 6.2 or 6.5 truck from napa!

 

[dmilkman589]

i know the exact problem. i just fixed it on mine yesterday... take off your fuel filter. there is a circle thing behind it. its like a presure switch or something. there are two wires coming off it. work it out with a screw driver. replace that o ring you see on it after removing it. fixes your problem..